Dressings for wounds and surgery are made of a variety of thin moisture vapor transmissive films as
disclosed in U.S. Pat. Nos. 3,483,018 and 3,645,835. These dressings are used in many applications and are impervious to bacteria and liquid water, but permit ambient oxygen to penetrate the dressing and allow moisture vapor to escape from beneath the dressing. Healing of a dressed wound is enhanced while the injury is protected. To provide desired levels of moisture vapor transmission from beneath the dressing and oxygen transfer from outside the dressing very thin films of polyurethane or other polymers are used.
These thin films are typically less than 10 mils thickness wherefore they are flexible, limp and flimsy. Consequently, such films can easily be applied over the contours of a biological subject and can be worn in relative comfort. The application of these films requires a layer of permeable adhesive coating to secure the film to the subject when the film is used as a dressing. A release sheet is used to cover the adhesive coating and protect the dressing prior to application. Removal of the release sheet prior to dressing application leaves the film and adhesive coating in a difficult condition for handling, application and use. In particular, the thin flexible film and adhesive coating require a delivery system to prevent the dressing from adhering to itself during attempted application to a biological subject. Dressings have been made with various tabbed release sheets and frame supports as disclosed in U.S. Pat. Nos. 2,734,503, 3,260,260, 3,349,745, 4,372,303, 4,485,809, 4,664,106. These delivery arrangements help by providing support for the thin flexible film during the application of the dressing.
Contamination of the adhesive surface must be prevented during and prior to application of the thin film dressing. With any dressing of the type described an over package is usually provided in order to maintain the sterile barrier until the dressing and its delivery system are used. These over packages include a wrapper composed of a top and bottom forming an enclosure to protect the product from contamination until unwrapping and use. As with any disposable medical product, the wrapper is designed for easy opening such as peeling the top from the bottom so the dressing can be removed without contamination of the biological subject side of the dressing.
Dressings of the type described have unnecessary expense in manufacture because of the number of components used for assisting delivery and for preventing contamination before removal from the package for use. Dressings of the type described do not permit or facilitate accurate control and placement of the dressing because the delivery system fails to provide sufficient support of the thin film backing and adhesive coating combination. Dressings of the type described require needless additional packaging material and assembly operations for purposes of establishing a sterile barrier.